1. Field of the Invention
The present invention relates to drill devices and more particularly to an improved keyless drill chuck that can hold drill bits of different diameters. More particularly, the present invention relates to an improved drill chuck apparatus that can support cylindrically shaped drill bits of different diameters using a tubular support member having different internal diameters defining two bore sections for holding smaller and larger drill bits respectively and wherein a plurality of conically shaped members registers against the drill bit and against scalloped or dished portions of the tubular member wall to cam the drill when rotational energy is applied, thereby holding the drill securely with respect to the tubular member.
2. General Background
During surgical procedures, rotary drills are often used, and most frequently in the orthopedic surgical field. Power and hand drills desirably work with conventional cylindrically shaped drill bits rather than with some specialized drill bit that has external projections or non-typical configurations.
One of the problems with commercially available electric drills, hand drills and the like in the orthopedic surgical industry is that of lost time. During surgical operations, a large number of personnel are often involved in the procedure. The expense of surgical operations can be measured in the expense per minute, which can be staggering. It is extremely important to utilize the operating room time as effectively as possible. This is especially important when considering limited tourniquet time in many surgical operations, not to mention extreme cost of the operating room on a minute by minute basis. Therefore, it is important to eliminate lost time associated with changing surgical instruments, modifying instruments or selecting instruments.
During orthopedic surgical procedures, it is common to use "trial" members before selecting a particular prothesis, support member, bone plate, drill bit or the like. It is common for surgeon to select a number of drill bits for a particular procedure before deciding upon a final diameter drill bit in a given situation. Selection of an appropriate drill bit for a given surgical procedure is a problem that has long plagued the art.
The connecting and disconnecting of drills and reamers to motor drives, electrical drills, hand drills and the like is major time consuming exercise during actual surgery. Therefore, there is a need for a drill apparatus that will allow the surgeon to quickly connect drills and reamers to power equipment without significant time loss, thus decreasing the amount of time for the actual operation.
A number of patents have issued which relate to drill chucks. Two early patents are U.S. Pat. No. 1,130,716 issued to Dressel entitled "Dental Tool" and U.S. Pat. No. 1,168,540 issued to Musselman and entitled "Chuck". The Dressel device is defined as a dental tool that comprises a tubular two part casing having a detachable connection between the parts thereof. The device provides a readily adjustable means for attaching sand paper or emory discs or similar abrasive grinding or buffing elements to the chuck of a standard dental engine. The Musselman device shows a hand drill with a chuck that enables insertion and fastening of the object in the holder to be performed quickly, easily and effectively. The chuck apparatus disclosed in the Musselman patent includes a body having a tool socket the wall of which is provided with a longitudinal slot and a straight longitudinal outer surface surrounding the slot. An outer shell is secured to enclose the socketed part of the body and provide it internally with an inwardly inclined part opposite the slot of the body. A gripping member is mounted to move longitudinally in the slot and the gripping member can be moved positively within the slot from a position exterior of the shell.
U.S. Pat. No. 2,405,772 provides a structure for supporting a tap in fixed relation to a supporting head so that relative axial and rotative movements are prevented, together with a means for assuring a smooth and uniform feeding of the tap without excessive demands upon the tap for procuring the required axial movement of the work.
The Cox U.S. Pat. No. 3,398,965 entitled "Quick Change Tool Holder" relates to a tool holder that is adapted to permit readily release and removal of one tool and replacement with another and wherein they are firmly held in proper operating position. The apparatus includes a tool receding bushing as a sliding fit relative to an outer holder body. The inside of the holder body has a cylindrically shaped bore that receives the bushing in sliding relation. A coil spring urges the bushing to an outer position. To insert a new tool, the user pushes upon the bore of the bushing relative to the tool body. This inward movement moves a plurality of locking balls into a locking position. The bushing can be rotated until apertures align with holes and a locking ball is dropped through the hole into the aperture. The sleeve or bushing is then rotated so that the just inserted ball travels in a groove until the next aperture is a lined with the ball feeding hole and another ball dropped into position. This operation is continued until the balls have been placed in all of the apertures. The locking balls extend into the tool receiving bore to grip the tool during use.
Another patent that discusses the use of a plurality of balls to lock a drill bit in position is the Linthicum U.S. Pat. No. 3,767,218. The '218 patent describes a chuck with a set of circumferentially spaced locking balls for retaining a tool in a chuck in accurate alignment and providing a driving connection between the chuck and the tool. The drill bit provides a hexagonally shaped shank to be secured within the chuck during use.
A self-gradually locking chuck is the subject of U.S. Pat. NO. 4,828,277 issued to DeBastiani. The DeBastiani device provides a locking chuck for drills or similar devices and is particularly directed to portable drills used in surgery. It includes a cylindrical sleeve which can be coaxially fixed to a rotating shaft, a ferrule having a conical section provided internally with lobes, a cylindrical portion at one of its ends for engagement with the sleeve and a cylindrical portion at the other end. A first mounting, perforated longitudinally by a hole, includes a central portion having locking jaws which are movable in holes in a direction convergent upon the axis of the chuck and two second mountings opposite the central body. A spring centering device is provided. A cylindrical ferrule is threaded to a part of the first mounting as it projects from the first mentioned ferrule. The first mounting and ferrule move axially in relation to each other and relation to the cylindrical sleeve in which the ferrule can be releasably secured to the cylindrical ferrule by a retaining device. The second mountings are releasably secured to the sleeve by a retaining device.
A tool driver that includes a shaft, shank, flange, clamp, and a retainer is the subject of U.S. Pat. No. 5,171,312 issued to Salyer and entitled "Tool Driver". The shaft has a longitudinal axis and opposed ends. The shank is joined to one end of the shaft. The flange is joined to one end of the shaft. The shank is joined to one end of the shaft. The flange is joined to the other end of the shaft and has an outwardly facing flange surface extending from the shaft transversely to the axis. The clamp has a clamping surface facing the flange surface. The clamp is movable axially relative to the flange to vary the separation of the surfaces. The retainer is operatively connected to the clamp and is movable relative to the clamp between a first position and a second position. The retainer, in the first position precludes relative movement of the clamp and the flange.
A similar Salyer patent (U.S. Pat. No. 5,171,313), relates to a tool driver. The Salyer '313 patent provides a tool driver with a body having a longitudinal axis and opposite ends. A boss is positioned at one of the ends. A tool collet is positioned at the other of the ends. A plunger is positioned with in the bore of the body. The body has a pair of oppositely disposed pins at least one of the pins being movable in relation to the body in response to movement of the plunger. An actuator is positioned on and connected to the plunger. The actuator and plunger move as an unit axially of the body between an at rest position and a static position. One pin is movable between an extend position and a retroactive position as the plunger and actuator move between an at rest position and a static position, whereby a tool can be positioned on the driver when the plunger and actuator are in their static position and held in operatable position on the tool driver when the plunger and actuator are in their at rest position.
A surgical apparatus useable for arthroscopic surgery is the subject of U.S. Pat. No. 5,192,292 issued to H. Cezana, et al. The Cezana patent discloses a surgical apparatus particularly used for arthroscopic surgery and which includes a tool insertable into a hollow, powered hand piece. The tool includes a hollow housing in which a driven member is rotatably sleeved, which driven member is provided at its forward end with a material working portion of suitable surgical type. The tool housing and driven member adjacent to receive corresponding pin-like elements on the hand piece for respectively angularly fixing the tool housing and rotatively driving the driven member.
A surgical drill chuck is the subject of U.S. Pat. No. 5,222,956 issued to Waldron. The Waldron patent discloses a drill that uses burs with circular grooves about the circumference that are polygon shaped in cross section but curved along the length of the bur so as to accept locking balls therein. The burs slide within a tubular drive shaft that has transverse holes therein to guide the locking balls. A cylindrical cam surrounds the drive shaft and the locking balls to urge the balls radially inward into the bur groove. The cam is spring loaded axially. A spring loaded central pin within the drive shaft slides between the balls and urges the balls radially outward when no bur is inserted. A thumb button is used to disengage the balls surrounding cam.
Each of the above discussed patents relates generally to the concept of a drill bit support member or drill chuck. Some of the above patents discuss drill chucks that are keyless and that they do not require a common drill key to manually disengage the drill bit from the chuck.